The command probes are executed before and after a client
command is executed, including any SQL statement that might be
executed during that period. Commands include operations such as
the initialization of the DB, use of the
COM_CHANGE_USER operation (supported by the
MySQL protocol), and manipulation of prepared statements. Many
of these commands are used only by the MySQL client API from
various connectors such as PHP and Java.
command-start(connectionid, command, user, host) command-done(status)
command-start: Triggered when a command
is submitted to the server.
connectionid: The connection ID of
the client executing the command.
command: An integer representing the
command that was executed. Possible values are shown in
the following table.
| Value | Name | Description |
|---|---|---|
| 00 | COM_SLEEP | Internal thread state |
| 01 | COM_QUIT | Close connection |
| 02 | COM_INIT_DB | Select database (USE ...) |
| 03 | COM_QUERY | Execute a query |
| 04 | COM_FIELD_LIST | Get a list of fields |
| 05 | COM_CREATE_DB | Create a database (deprecated) |
| 06 | COM_DROP_DB | Drop a database (deprecated) |
| 07 | COM_REFRESH | Refresh connection |
| 08 | COM_SHUTDOWN | Shutdown server |
| 09 | COM_STATISTICS | Get statistics |
| 10 | COM_PROCESS_INFO | Get processes (SHOW PROCESSLIST) |
| 11 | COM_CONNECT | Initialize connection |
| 12 | COM_PROCESS_KILL | Kill process |
| 13 | COM_DEBUG | Get debug information |
| 14 | COM_PING | Ping |
| 15 | COM_TIME | Internal thread state |
| 16 | COM_DELAYED_INSERT | Internal thread state |
| 17 | COM_CHANGE_USER | Change user |
| 18 | COM_BINLOG_DUMP | Used by a replication slave or mysqlbinlog to initiate a binary log read |
| 19 | COM_TABLE_DUMP | Used by a replication slave to get the master table information |
| 20 | COM_CONNECT_OUT | Used by a replication slave to log a connection to the server |
| 21 | COM_REGISTER_SLAVE | Used by a replication slave during registration |
| 22 | COM_STMT_PREPARE | Prepare a statement |
| 23 | COM_STMT_EXECUTE | Execute a statement |
| 24 | COM_STMT_SEND_LONG_DATA | Used by a client when requesting extended data |
| 25 | COM_STMT_CLOSE | Close a prepared statement |
| 26 | COM_STMT_RESET | Reset a prepared statement |
| 27 | COM_SET_OPTION | Set a server option |
| 28 | COM_STMT_FETCH | Fetch a prepared statement |
user: The user executing the command.
host: The client host.
command-done: Triggered when the command
execution completes. The status argument
contains 0 if the command executed successfully, or 1 if the
statement was terminated before normal completion.
The command-start and
command-done probes are best used when
combined with the statement probes to get an idea of overall
execution time.